Abatement and strip process chamber in a dual loadlock configuration

ABSTRACT

Embodiments of the present invention provide a dual load lock chamber capable of processing a substrate. In one embodiment, the dual load lock chamber includes a chamber body defining a first chamber volume and a second chamber volume isolated from one another. Each of the lower and second chamber volumes is selectively connectable to two processing environments through two openings configured for substrate transferring. The dual load lock chamber also includes a heated substrate support assembly disposed in the second chamber volume. The heated substrate support assembly is configured to support and heat a substrate thereon. The dual load lock chamber also includes a remote plasma source connected to the second chamber volume for supplying a plasma to the second chamber volume.

BACKGROUND

1. Field

Embodiment of the present invention generally relates to a method andapparatus for fabricating devices on a semiconductor substrate. Moreparticularly, embodiments of the present invention relate to load lockchamber including two chamber volumes and at least one chamber volume isconfigured for processing a substrate.

2. Description of the Related Art

Embodiment of the present invention generally relates to a method andapparatus for fabricating devices on a semiconductor substrate. Moreparticularly, embodiments of the present invention relate to load lockchamber including two load locks and capable for processing a substrate.

Ultra-large-scale integrated (ULSI) circuits may include more than onemillion electronic devices (e.g., transistors) that are formed on asemiconductor substrate, such as a silicon (Si) substrate, and cooperateto perform various functions within the device. Typically, thetransistors used in the ULSI circuits are complementarymetal-oxide-semiconductor (CMOS) field effect transistors. A CMOStransistor has a gate structure comprising a polysilicon gate electrodeand gate dielectric, and is disposed between a source region and drainregions that are formed in the substrate.

Plasma etching is commonly used in the fabrication of transistors andother electronic devices. During plasma etch processes used to formtransistor structures, one or more layers of a film stack (e.g., layersof silicon, polysilicon, hafnium dioxide (HfO₂), silicon dioxide (SiO₂),metal materials, and the like) are typically exposed to etchantscomprising at least one halogen-containing gas, such as hydrogen bromide(HBr), chlorine (Cl₂), carbon tetrafluoride (CF₄), and the like. Suchprocesses cause a halogen-containing residue to build up on the surfacesof the etched features, etch masks, and elsewhere on the substrate.

When exposed to a non-vacuumed environment (e.g., within factoryinterfaces or substrate storage cassettes) and/or during consecutiveprocessing, gaseous halogens and halogen-based reactants (e.g., bromine(Br₂), chlorine(Cl₂), hydrogen chloride (HCl), and the like) may bereleased from the halogen-containing residues deposited during etching.The released halogens and halogen-based reactants create particlecontamination and cause corrosion of the interior of the processingsystems and factory interfaces, as well as corrosion of exposed portionsof metallic layers on the substrate. Cleaning of the processing systemsand factory interfaces and replacement of the corroded parts is a timeconsuming and expensive procedure.

Several processes have been developed to remove the halogen-containingresidues on the etched substrates. For example, the etched substrate maybe transferred into a remote plasma reactor to expose the etchedsubstrate to a gas mixture that converts the halogen-containing residuesto non-corrosive volatile compounds that may be out-gassed and pumpedout of the reactor. However, such process requires a dedicated processchamber along with an additional step, causing increased tool expense,reduced manufacturing productivity and throughput, resulting in highmanufacturing cost.

Therefore, there is a need for an improved method and apparatus forremoving halogen-containing residues from a substrate.

SUMMARY

Embodiments of the present invention generally provide apparatus andmethods for processing a substrate. Particularly, embodiments of thepresent inventions provide a dual load lock chamber capable ofprocessing a substrate, for example by exposing the substrate positionedtherein to a reactive species.

One embodiment of the present invention provides a load lock chamber.The load lock chamber includes a chamber body defining a first chambervolume and a second chamber volume isolated from one another. The firstchamber volume is selectively connectable to two processing environmentsthrough two openings configured for substrate transferring. The secondchamber volume is selectively connected to at least one of the twoprocessing environments. The load lock chamber further includes a heatedsubstrate support assembly disposed in the second chamber volume and aremote plasma source connected to the second chamber volume forsupplying a plasma to the second chamber volume. The heated substratesupport assembly is configured to support and heat a substrate thereon.

One embodiment of the present invention provides a dual load lockchamber. The dual load lock chamber includes a chamber body defining afirst chamber volume and a second chamber volume isolated from oneanother. Each of the lower and second chamber volumes is selectivelyconnectable to two separate adjacent environments through two openingsconfigured for substrate transferring. The dual load lock chamber alsoincludes a heated substrate support assembly disposed in the secondchamber volume. The heated substrate support assembly is configured tosupport and heat a substrate thereon. The dual load lock chamber alsoincludes a remote plasma source connected to the second chamber volumefor supplying reactive species to the second chamber volume.

Another embodiment of the present invention provides a dual load lockchamber. The dual load lock chamber includes a chamber body defining asecond chamber volume and a lower lock load volume isolated from oneanother, a substrate support assembly configured to support a substratedisposed in the first chamber volume, and a heated substrate supportassembly configured to support and heat a substrate disposed in thesecond chamber volume. Each of the lower and second chamber volumes isselectively connectable to two separate adjacent environments throughtwo openings configured for substrate transferring. The dual load lockchamber also includes a shower head assembly disposed over the heatedsubstrate support assembly, wherein the showerhead assembly isconfigured to distribute one or more processing gas to the secondchamber volume.

Yet another embodiment of the present invention provides a method forremoving halogen-containing residues from a substrate. The methodincludes transferring a substrate to a substrate processing systemthrough an incoming load lock of a double load lock chamber coupled tothe substrate processing system, and etching the substrate in thesubstrate processing chamber with chemistry comprising halogen. Themethod also includes removing halogen-containing residues from theetched substrate in an outgoing load lock of the double load lockchamber, wherein the outgoing load lock is isolated from the incomingload lock in a single chamber body. Removing halogen-containing residuesincludes heating the etched substrate on a heated substrate supportassembly of the outgoing load lock, and flowing a processing gas to theoutgoing load lock.

The method described above, wherein removing halogen-containing residuesincludes creating a symmetrical processing environment using a hoopliner surrounding the heated substrate support assembly.

The method described above, wherein flowing the processing gas mayinclude generating a plasma of the processing gas in a remote plasmasource.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the presentinvention can be understood in detail, a more particular description ofthe invention, briefly summarized above, may be had by reference toembodiments, some of which are illustrated in the appended drawings. Itis to be noted, however, that the appended drawings illustrate onlytypical embodiments of this invention and are therefore not to beconsidered limiting of its scope, for the invention may admit to otherequally effective embodiments.

FIG. 1 is a schematic sectional view of a dual load lock chamberaccording to one embodiment of the present invention.

FIG. 2 is a schematic sectional view of the dual load lock chamber ofFIG. 1 with a lifting hoop in a loading/unloading position.

FIG. 3 is a schematic top view of a second chamber volume of the dualload lock chamber according to one embodiment of the present invention.

FIG. 4 is a schematic top view of a first chamber volume of the dualload lock chamber according to one embodiment of the present invention.

FIG. 5 is a schematic perspective view of a first chamber body of a dualload lock chamber according to one embodiment of the present invention.

FIG. 6 is a perspective sectional view showing the first chamber bodyand the second chamber body assembled together.

FIG. 7 is a perspective sectional view illustrating pumping channelsformed in the second chamber body and the first chamber body with aheater substrate support assembly removed.

FIG. 8 is a schematic section view a dual load lock chamber according toanother embodiment of the present invention.

FIG. 9 is a schematic plan view of a substrate processing systemincluding dual load lock chambers according to embodiments of thepresent invention.

FIG. 10 is a flow diagram illustrating a method for processing asubstrate according to one embodiment of the present invention.

FIG. 11 is a flow diagram illustrating a method for processing asubstrate according to another embodiment of the present invention.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures. It is contemplated that elements disclosed in oneembodiment may be beneficially utilized on other embodiments withoutspecific recitation

DETAILED DESCRIPTION

Embodiments of the present invention provide apparatus and methods forfabricating devices on a semiconductor substrate. More particularly,embodiments of the present invention relate to a dual load lock chamberincluding two isolated chamber volumes, wherein at least one chambervolume is configured for processing a substrate, for example, byexposing the substrate to reactive species.

One embodiment of the present invention provides a load lock chamberhaving at least two isolated chamber volumes formed in a body assembly.The two isolated chamber volumes may be vertically stacked or disposedside-by-side. The two chamber volumes are independently operable toincrease throughput. In one embodiment, a first chamber volume isconfigured to expose a substrate disposed therein to reactive species tothe substrate disposed therein, for example removing halogen residualfrom the substrate or removing photoresist from the substrate. Thesecond chamber volume is utilized only to exchange between adjoiningenvironments, such as an environment of a factory interface and transferchamber. One embodiment of the present invention provides a load lockchamber including a thin heated substrate support for heating thesubstrate therein and a showerhead disposed over the thin heatedsubstrate support for uniformly supplying one or more processing gasesto the load lock chamber. In one embodiment, the showerhead is connectedto a remote plasma source to supply reactive species to the load lockchamber. The load lock chamber of the present invention may also includea hoop liner to create a symmetrical processing environment within thechamber volume utilized to process the substrate. In one embodiment ofthe present invention, the hoop liner may be coupled to one of more liftfingers configured to exchange substrates with substrate transfer robotsdisposed outside of the load lock chamber.

FIG. 1 is a schematic sectional view of a dual load lock chamber 100according to one embodiment of the present invention. The dual load lockchamber 100 includes a first chamber volume 110 for transferring asubstrate 104, and a second chamber volume 120 for transferring andprocessing a substrate 104. The second chamber volume 120 and the firstchamber volume 110 are vertically stacked together and are isolated fromone another.

The dual load lock chamber 100 includes a chamber body assembly 103. Inone embodiment, the chamber body assembly 103 includes a first chamberbody 111 and a second chamber body 121 coupled together to define aunitary structure housing the first and second chamber volumes 120, 110.In one embodiment, the first chamber body 111 and the second chamberbody 121 are vertically stacked. Although the first chamber body 111 isshown stack below the second chamber body 121, it is contemplated thefirst chamber body 111 may be stack above the second chamber body 121 orpositioned horizontally side-by-side.

The second chamber volume 120 of the dual load lock chamber 100 has ashowerhead 129, a heated substrate support assembly 132, and a lift hoopassembly 144. The showerhead 129 is disposed over the heated substratesupport assembly 132. The lift hoop assembly 144 is configured toconfine a processing environment within the second chamber volume 120,as well as being operable to load and unload substrates from the heatedsubstrate support assembly 132 and substrate transfer robots (notshown).

The second chamber volume 120 is defined by sidewalls 122 of the secondchamber body 121, a lid liner 127 disposed over the sidewalls 122, abottom wall 123 of the second chamber body 121, and a top wall 118 ofthe first chamber body 111. The lid liner 127 has an inner lip 127 aforming a central opening 127 c. The inner lip 127 a holds a showerhead129 and a source adapter plate 128. In one embodiment, the lid liner 127is removably disposed over the second chamber body 121 to allow accessto chamber components.

The showerhead 129 includes a face plate 129 d having a plurality ofthrough holes 129 a formed therethrough and a back plate 129 c having acentral opening 129 e. The face plate 129 d and the back plate 129 cenclose an inner volume 129 b. The inner volume 129 b serves as a plenumfor enhancing the radial uniformity of gas provided into the secondchamber volume 120 through the through holes 129 a formed through theface plate 129 d.

The source adapter plate 128 is disposed above the back plate 129 c ofthe showerhead 129. The source adapter plate 128 has a central opening128 a matches with the central opening 129 e of the showerhead 129. Aremote plasma source 130 is in fluid communication with the inner volume129 b of the showerhead 129 through a quartz insert 131 disposed in theopenings 129 e and 128 a. The disassociated reactive species from theremote plasma source 130 enters the second chamber volume 120 throughthe quart insert 131 to the inner volume 129 b of the showerhead 129,then through the through holes 129 a of the showerhead 129 to the secondchamber volume 120.

In one embodiment, the showerhead 129 is fabricated formed from quartzsuch that surfaces of the inner volume 129 b exposed to the reactivespecies within the plenum is lined by quartz. The quartz insert 131 andthe showerhead 129 shield metal chamber components from being exposed tothe reactive species provided from the remote plasma source 130, thussubstantially reducing species recombination, attack of metal chambercomponents and particle generation.

The remote plasma source 130 is generally connected to one or more gaspanels for supplying one or more processing gas to the upper chambervolume 110 through the remote plasma source 130. In one embodiment, theremote plasma source 130 is connected to a first gas panel 101configured for providing processing gases for an abatement process toremove residual material after etching and a second gas panel 102configured for providing processing gases for an ashing process toremove photoresist.

The heated substrate support assembly 132 is configured to fit in thesecond chamber volume 120 of the dual load lock chamber 100. The heatedsubstrate support assembly 132 is installed to be substantiallythermally insulated from the chamber body assembly 103. In oneembodiment, the heated substrate support assembly 132 is configured toheat the substrate 104 up to 300° C. while the chamber body assembly 103remains cool.

In one embodiment, the heated substrate support assembly 132 includes anupper heater plate 133, a lower heater plate 134 attached to the upperheater plate 133, and a heater 135 disposed between the upper heaterplate 133 and the lower heater plate 134. In one embodiment, the heater135 may be disposed in channels formed on an upper surface of the lowerheater plate 134. The heater 135 may be a resistive heater or conduitsarranged to flow a heat transfer fluid. The upper heater plate 133 andthe lower heater plate 134 may be joined together by bolts, welding orbrazing. In one embodiment, the upper heater plate 133 and the lowerheater plate 134 may be formed from metal, such as aluminum.

The upper heater plate 133 is configured to support the backside 104 bof the substrate 104. In one embodiment, the lower heater plate 134 hasan outer diameter larger than the outer diameter of the upper heaterplate 133. A focus ring 151 may be disposed on an outer edge 134 a ofthe lower heater plate 134 exposed radially outwards of the upper heaterplate 133. The focus ring 151 surrounds the upper heater plate 133 andthe substrate 104 disposed thereon. The focus ring 151 functions toretain the substrate 104 and to modify processing rate around an edgearea of the substrate 104 during processing. In one embodiment, thefocus ring 151, the upper and lower heater plates 133, 134 may havematching cut outs 155 configured to provide passage for lift fingers147.

The heated substrate support assembly 132 is mounted on a thermalinsulator 143 disposed on the top wall 118 of the first chamber body 111through a central opening 123 a in the bottom wall 123 of the secondchamber body 121. In one embodiment, a recess 118 a may be formed on thetop wall 118 of the first chamber body 111. The recess 118 a may allowvacuum ports formed in the first chamber body 111 to connect with thesecond chamber volume 120. The heated substrate support assembly 132does not directly contact the chamber body assembly 103. The thermalinsulator 143 may be formed from a thermal insulative material, such asa ceramic, to prevent thermal exchange between the heated substratesupport assembly 132 and the chamber body assembly 103 including boththe second chamber body 121 and the first chamber body 111.

The thermal insulator 143 is positioned to center the heated substratesupport assembly 132 relative to other components in the second chambervolume 120, for example the showerhead 129, and the lift hoop assembly144. In one embodiment, the thermal insulator 143 aligns with a centralaxis 132 a of the heated substrate support assembly 132 to ensure thatthe heated substrate support assembly 132 remains centered duringthermal expansion.

A cantilever tube 136 extends from a backside 134 b near the center ofthe lower heater plate 134. The cantilever tube 136 extends radiallyoutwards to connect with a vertical tube 137 disposed through an opening153 of the second chamber body 121 and an opening 152 of the firstchamber body 111. The tubes 136, 137 do not contact the second chamberbody 121 or the first chamber body 111 to further avoid heat exchangebetween the heated substrate support assembly 132 and the chamber bodies111, 121. The cantilever tube 136 and the vertical tube 137 provide apassage for power supplies, sensors and other wiring to be used by theheated substrate support assembly 132. In one embodiment, a heater powersource 138, a sensor signal receiver 139 and a chucking control unit 140are wired to the heated substrate support assembly 132 through thepassage in the cantilever tube 136 and the vertical tube 137. In oneembodiment, the chucking control unit 140 is configured to provide avacuum chucking mechanism.

A cooling adaptor 141 is coupled to the vertical tube 137 and the firstchamber body 111 from outside of the first chamber body 111. The coolingadaptor 141 has cooling channels 141 a formed therein. A source forcooling fluid 142 is connected to the cooling channels 141 a to providecooling to the cooling adaptor 141 and the vertical tube 137, thecantilever tube 136, and other components of the heated substratesupport assembly 132. The cooling adapter 141 generally stays coolduring processing, thus, functioning as a thermal insulator between theheated substrate support assembly 133 and the chamber body assembly 103.

In one embodiment, bi-metal connectors may be used for connectingvarious parts of the heated substrate support assembly 132 to provideuniform temperature control.

A more detailed description of the heated substrate support assembly 132can be found in U.S. Provisional Patent Application Ser. No. 61/448,018,filed Mar. 1, 2011, entitled “Thin Heater Substrate support” (Docket No.15750).

The dual load lock chamber 100 also includes the lift hoop assembly 144for transfer substrates between exterior robots and the heated substratesupport assembly 132 and for providing a symmetrical processingenvironment in the second chamber volume 120. The lift hoop assembly 144include a ring-shaped hoop body 146 disposed within the second chambervolume 120 around the heated substrate support assembly 132. The hoopbody 146 is coupled to a lift 160 disposed in an outer region of thesecond chamber volume 120. The lift 160 moves the hoop body 146vertically within the second chamber volume 120. In one embodiment, thelift 160 includes a bellows 161 for vertical movements. The lift 160 maybe coupled to a motorized actuator 169 disposed outside the chamber bodyassembly 103.

Three or more lifting fingers 147 are attached to the hoop body 146. Thelifting fingers 147 extend vertically downwards and radially inwardsfrom the hoop body 146. The lifting fingers 147 are configured totransfer substrates between the heated substrate support assembly 132and substrate transfer devices, such as robots, outside the secondchamber volume 120. Tips 147 a of the lifting fingers 147 form asubstrate support surface configured to support the substrate 104 atseveral points near an edge region of the substrate 104.

FIG. 1 shows the lift hoop assembly 144 in an upper position forsubstrate exchange with exterior substrate transfer devices. FIG. 2 is aschematic sectional view of the dual load lock chamber 100 the lift hoopassembly 144 in a lower position for substrate processing.

When the hoop body 146 is at a lower position shown in FIG. 2, thelifting fingers 147 are positioned below the upper surface 133 a of theupper heater plate 133. As the hoop body 146 rises to the upperposition, the lifting fingers 147 move to contact with and lift thesubstrate 104 from the heated substrate support assembly 132. While thehoop body 146 is at the upper position shown in FIG. 1, externalsubstrate transferring device (not shown) can enter the second chambervolume 120 through one of the ports to remove the substrate 104 from thelifting fingers 147 and subsequently place a new substrate 104 onto thelifting fingers 147. When the hoop body 146 lowers to the lower positionagain, the new substrate 104 positioned on the lifting fingers 147 isplaced on the heated substrate support assembly 132 for processing.

A hoop liner 145 is attached to the hoop body 146. The hoop liner 145extends vertically upwards from the hoop body 146. In one embodiment,the hoop liner 145 is a ring having a substantially flat cylindricalinner wall 145 a. In one embodiment, the height 145 b of the inner wall145 a of the hoop liner 145 is much greater than the thickness of theheated substrate support assembly 132 and an inner diameter greater thanthe outer diameters of the heated substrate support assembly 132 and theshowerhead 129 so that the hoop liner 145 can create a processingenvironment around the heated substrate support assembly 132 and theshowerhead 129. When the hoop body 146 is in the upper position, shownin FIG. 1, the hoop liner 145 may enter into a cavity 127 b formedwithin the lid liner 127. When the hoop body 146 is in the lowerposition, the cylindrical inner wall 145 a of the hoop liner 145 createsa circular confinement wall within the second chamber volume 120 aroundthe substrate 104 and the region immediately above the heated substratesupport assembly 132, therefore, providing a symmetrical processingenvironment for the substrate 104. In one embodiment, the height 145 bof the hoop liner 145 is sufficiently large enough to cover the verticalspace between the face plate 129 d of the showerhead 129 and the heatedsubstrate support assembly 132. In one embodiment, the hoop liner 145may be formed from quartz.

A more detailed description of the lift hoop assembly 144 can be foundin U.S. Provisional Patent Application Ser. No. 61/448,012, filed Mar.1, 2011, entitled “Method and Apparatus for Substrate Transfer andRadical Confinement” (docket No. 15745).

The first chamber volume 110 is defined by the first chamber body 111and a chamber bottom 112 attached to the first chamber body 111. Thefirst chamber body 111 has a top wall 118 and sidewalls 119. The topwall 118, side walls 119 and the chamber bottom 112 enclose the firstchamber volume 110. A substrate support mechanism configured to supporta substrate 104 and exchange substrate with substrate transfer devices,such as substrate transfer robots, may be disposed in the first chambervolume 110. In one embodiment, the substrate support mechanism includesthree or more supporting pins 113 for supporting the substrate 104 fromits backside 104 b. In one embodiment, the supporting pins 113 may befixedly extended from the first chamber body 111 or the chamber bottom112. The supporting pins 113 are positioned to interact with substratetransferring devices.

The second chamber volume 120 and the first chamber volume 110 arecoupled to a vacuum system 150. In one embodiment, pressures in thesecond chamber volume 120 and the first chamber volume 110 arecontrolled independently from one another.

FIG. 3 is a schematic top view of a second chamber body 121 with theshowerhead 129 removed. The second chamber body 121 includes sidewalls122 and a bottom wall 123. The bottom wall 123 is formed to match thetop wall 118 of the first chamber body 111 to form a closed chambervolume, passages for vacuum and utilities (details to follow). Twoopenings 325 are formed through the sidewalls 122 to allow substratetransferring. A slit valve door may be attached outside of each opening325 thus providing interface between the second chamber volume 120 andtwo processing environments.

FIG. 4 is a schematic top view of the first chamber volume 110 of thedual load lock chamber 100. Two openings 416 are formed through thesidewalls 119 of the first chamber body 111 to allow substrate transferbetween two processing environments, for example a vacuum transferchamber and an atmospheric factory interface (both not shown). A slitvalve door may be attached outside of each opening 416 to selectivelyseal the first chamber volume 110 from the two processing environments,such as the vacuum transfer chamber and the atmospheric factorinterface. The first chamber body 111 may have a lower vacuum port 415open to the first chamber volume 110 for pumping the first chambervolume 110.

In one embodiment, an upper vacuum port 454 is also formed through thefirst chamber body 111 for pumping the second chamber volume 120.

FIG. 5 is a schematic perspective view of the first chamber body 111according to one embodiment of the present invention. The recess 118 ais formed on the top wall 118 of the first chamber body 111. The recess118 a allows the heated substrate support assembly 132 to sit low in thesecond chamber volume 120 thus reducing the second chamber volume 120. Acenter notch 543 may be formed within the recess 118 a for anchoring thethermal insulator 143 (shown in FIG. 1) for supporting the heatedsubstrate support assembly 132. The upper vacuum port 454 is formedthrough the sidewalls 119 of the first chamber body 111 and opens to therecess 118 a formed in the top wall 118 of the first chamber body 111.Thus, the recess 118 a also allows pumping channel to the second chambervolume 120 to form within the first chamber body 111. Alternatively, thevacuum port 454 may be formed outside the recess 118 a to match with aport formed on the bottom wall 123 of the second chamber body 121.

In one embodiment, at least one gland 511 a is formed around the recess118 a. A seal may be disposed in each gland 511 a to form a vacuum sealbetween the second chamber body 121 and the first chamber body 111. Inone embodiment, two glands 511 a may be formed on the top wall 118 ofthe first chamber body 111 to provide increased vacuum seal.

FIG. 6 is a perspective sectional view showing the second chamber body121 and the first chamber body 111 in an assembled together. The centralopening 123 a formed on the bottom wall 123 of the second chamber body121 connects the interior of the second chamber volume 120 with therecess 118 a on the top wall 118 of the first chamber body 111. Thus,the upper vacuum port 454 is in fluid communication with the secondchamber volume 120 when the second chamber body 121 is attached to thefirst chamber body 111.

FIG. 7 is a perspective sectional view of the second chamber body 121and the first chamber body 111 with the heater substrate supportassembly 132 removed. In FIG. 7, the lower vacuum port 415 is shown. Thesecond chamber body 121 and the first chamber body 111 can be joinedtogether with various methods to obtain a vacuum seal. In oneembodiment, the second chamber body 121 is bolted to the first chamberbody 111. In another embodiment, the first chamber body 111 and thesecond chamber body 121 may be brazed together to reduce risk of leakand to eliminate issues with tolerance.

FIG. 8 is a schematic section view a dual load lock chamber 800according to another embodiment of the present invention. The dual loadlock chamber 800 is similar to the dual load lock chamber 100 exceptthat a lamp assembly 810 in the dual load lock chamber 800 is used inplace of the remote plasma source 130 in the dual load lock chamber 100.A quartz window 811 is disposed over the lid liner 127. The lampassembly 810 is positioned outside the quartz window 811. Radiant energyfrom the lamp assembly 810 can be directed to the second chamber volume120 through the quartz window 811. A gas source 812 is in fluidcommunication with the second chamber volume 120 to provide processinggas and/or inert gas for purging.

FIG. 9 is a schematic plan view of a substrate processing system 900that includes one or more dual load lock chambers 100 according toembodiments of the present invention. Dual load lock chamber 800 canalso be used in place of dual load lock chambers 100.

The system 900 includes a vacuum-tight processing platform 904, afactory interface 902, and a system controller 944. The platform 904includes a plurality of processing chambers 918 and at least one dualload-lock chamber 100 that are coupled to a vacuum substrate transferchamber 936. In one embodiment, the transfer chamber 936 may have foursides 920. Each side 920 is configured to connect with a pair ofprocessing chambers 918 or load lock chambers 100. Six processingchambers 918 are coupled to three sides 920 of the transfer chamber 936and two dual load lock chambers 100 are coupled the fourth side 920 ofthe transfer chamber 936 as shown in FIG. 9. The factory interface 902is coupled to the transfer chamber 936 by the dual load lock chambers100.

In one embodiment, the factory interface 902 comprises at least onedocking station 908 and at least one factory interface robot 914 tofacilitate transfer of substrates. The docking station 908 is configuredto accept one or more front opening unified pod (FOUP). Four FOUPS 906are shown in the embodiment of FIG. 9. The factory interface robot 914having a blade 916 disposed on one end of the robot 914 is configured totransfer the substrate from the factory interface 902 to the processingplatform 904 for processing through the dual load lock chambers 100.

Each of the dual load lock chambers 100 have two ports coupled to thefactory interface 902 and two ports coupled to the transfer chamber 936.The dual load lock chambers 100 are coupled to a pressure control system(not shown) which pumps down and vents the dual load lock chambers 100to facilitate passing the substrate between the vacuum environment ofthe transfer chamber 936 and the substantially ambient (e.g.,atmospheric) environment of the factory interface 902.

The transfer chamber 936 has a vacuum robot 937 disposed therein fortransferring a substrate 924 among the dual load lock chambers 100 andthe processing chambers 918. In one embodiment, the vacuum robot 937 hastwo blades 940 each capable of transferring a substrate 924 among thedual load lock chambers 100 and the processing chambers 918. In oneembodiment, the vacuum robot 937 is configured to simultaneouslytransfer two substrates 924 to two processing chambers 918 or two loadlocks 100.

In one embodiment, at least one process chambers 918 is an etch chamber.For example, the etch chamber may be a Decoupled Plasma Source (DPS)chamber available from Applied Materials, Inc. The DPS etch chamber usesan inductive source to produce high-density plasma and comprises asource of radio-frequency (RF) power to bias the substrate.Alternatively, at least one of the process chambers 918 may be one of aHART™, E-MAX®, DPS®, DPS II, PRODUCER E, or ENABLER® etch chamber alsoavailable from Applied Materials, Inc. Other etch chambers, includingthose from other manufacturers, may be utilized. The etch chambers mayuse a halogen-containing gas to etch the substrate 924 therein. Examplesof halogen-containing gas include hydrogen bromide (HBr), chlorine(Cl₂), carbon tetrafluoride (CF₄), and the like. After etching thesubstrate 924, halogen-containing residues may be left on the substratesurface.

The halogen-containing residues may be removed by a thermal treatmentprocess in the dual load lock chambers 100. For example, a thermaltreatment process may be performed in the second chamber volume 120 ofone or both dual load lock chambers 100. Alternatively, an ashingprocess may be performed in the second chamber volume 120 of one or bothdual load lock chambers 100.

The system controller 944 is coupled to the processing system 900. Thesystem controller 944 controls the operation of the system 900 using adirect control of the process chambers 918 of the system 900 oralternatively, by controlling the computers (or controllers) associatedwith the process chambers 918 and the system 900. In operation, thesystem controller 944 enables data collection and feedback from therespective chambers and system controller 944 to optimize performance ofthe system 900.

The system controller 944 generally includes a central processing unit(CPU) 938, a memory 940, and support circuit 942. The CPU 938 may be oneof any form of a general purpose computer processor that can be used inan industrial setting. The support circuits 942 are conventionallycoupled to the CPU 938 and may comprise cache, clock circuits,input/output subsystems, power supplies, and the like. The softwareroutines, such as a method 1000 for removing halogen-containing residuesdescribed below with reference to FIG. 10 and/or a method 1100 forashing described with reference to FIG. 11, when executed by the CPU938, transform the CPU 938 into a specific purpose computer (controller)944. The software routines may also be stored and/or executed by asecond controller (not shown) that is located remotely from the system900.

FIG. 10 is a flow chart illustrating a method 1000 for processing asubstrate according to one embodiment of the present invention.Particularly, the method 1000 is configured to remove halogen-containingresidue from a substrate. The method 1000 may be performed in theprocessing system 900 as described in FIG. 8. It is contemplated thatthe method 1000 may be performed in other suitable processing systems,including those from other manufacturers.

The method 1000 begins at box 1010 by transferring a substrate having alayer disposed thereon from one of the FOUPs 906 to the dual load lockchamber 100 and pumping down the chamber volume containing the substrateto a vacuum level equal to that of the transfer chamber 936. In oneembodiment, the substrate transferred to the dual load lock chamber 100may be transferred from the factory interface 902 only into the firstchamber volume 110 of the dual load lock chamber 100. In this manner,cross contamination between processed and unprocessed substrate isbeneficially reduced.

In another embodiment, the substrate transferred to the dual load lockchamber 100 may be preheated to a predetermined temperature by theheated substrate support assembly 132 in the second chamber volume 120of the load lock chamber 100. In one embodiment, the substrate may bepreheated to a temperature between about 20 degrees Celsius and about400 degrees Celsius.

At box 1020, after the pressure within the dual load lock chamber 100and the transfer chamber 936 are substantially equal, the vacuum robot937 transfers the substrate from the dual load lock chamber 100 to oneof the processing chambers 918.

At box 1030, the substrate is etched in one of the processing chamber918 to form desired features and patterns on the substrate.

In one embodiment, the substrate is etched in one of the processingchambers 918 by supplying a gas mixture having at least ahalogen-containing gas. The patterned mask may include photoresistand/or hardmask. Suitable examples of halogen-containing gas include,but not limited to, hydrogen bromide (HBr), chlorine (Cl₂), carbontetrafluoride (CF₄), and the like. In an exemplary embodiment suitablefor etching polysilicon, the gas mixture supplied to the processingchamber 918 provides a gas mixture including hydrogen bromide (HBr) andchlorine (Cl₂) gas at a flow rate between about 20 sccm and about 300sccm, such as between 20 sccm and about 60 sccm, for example about 40sccm. The hydrogen bromide (HBr) and chlorine (Cl₂) gas may have a gasratio ranging between about 1:0 and about 1:30, such as about 1:15. Aninert gas may be supplied with the gas mixture to the processing chamber918. Suitable examples of inert gas may include nitrogen (N₂), argon(Ar), helium (He) and the like. In one embodiment, the inert gas, suchas N₂, may supplied with the gas mixture at a flow rate between about 0sccm and about 200 sccm, such as between about 0 sccm and about 40 sccm,for example about 20 sccm. A reducing gas, such as carbon monoxide (CO)may be supplied with the gas mixture. The plasma power for the etchprocess may be maintained between about 200 Watts and about 3000 Watts,such as about 500 Watts and about 1500 Watts, for example about 1100Watts, and the bias power may be maintained between about 0 Watts andabout 300 Watts, such as about 0 Watts and about 80 Watts, for exampleabout 20 Watts,. The process pressure may be controlled at between about2 mTorr and about 100 mTorr, such as between about 2 mTorr and about 20mTorr, for example about 4 mTorr, and the substrate temperature may bemaintained at between about 0 degrees Celsius and about 200 degreesCelsius, such as between about 0 degrees Celsius and about 100 degreesCelsius, for example about 45 degrees Celsius.

During etching process, the etched materials may combine with thecomponents of the etchant chemistry, as well as with the components ofthe mask layers, if any, and by-products of the etch process, therebyforming halogen-containing residues. In one embodiment, the materials onthe substrate to be etched may include photoresist layer, hard masklayer, bottom anti-reflective coating (BARC), polysilicon, crystallinesilicon, gate oxide, metal gate, such as Titanium nitride (TiN), andhigh-k materials, such as aluminum oxide (Al₂O₃), hafnium containingoxide. Suitable examples of hard mask layer include silicon nitride,TEOS, silicon oxide, amorphous carbon, and silicon carbide. Thehalogen-containing residues deposit on the surfaces of the substrate.The halogen-containing residue may release (e.g., outgas) gaseousreactants, such as bromine(Br₂), chlorine(Cl₂), hydrogen chloride (HCl),hydrogen bromine (HBr) and the like, if exposed to atmospheric pressuresand/or water vapor. The release of such reactants may cause corrosionsand particle contamination of the processing apparatus and factoryinterfaces during substrate transfer, such as the vacuum-tightprocessing platform 904 and the factory interface 902 as described inFIG. 1. In embodiments where metallic layers, such as Cu, Al, W, areexposed to the substrate surface, the metallic layer may be corroded bythe released gaseous reactants if they are not removed by the inventiveprocess described below, thereby adversely deteriorating the performanceof devices formed on the substrate.

Halogens may also be present on the surface of substrates that areprocessed in a vacuum environment in a manner other than etching.Therefore, it is contemplated that halogens may be removed from thosesubstrates using the method and apparatus described herein.

At box 1040, the processed (e.g., etched) substrate is transferred tothe second chamber volume 120 of the dual load lock chamber 100 toremove the halogen-containing residues from the substrate generatedduring processing of box 1030 prior to exposure to atmosphericconditions or water vapor in the factory interface or other location.After etch processing, the vacuum robot 937 in the transfer chamber 936transfers the etched substrate from one of the processing chambers 918to the lifting fingers 147 in the second chamber volume 120 of the loadlock chamber 100. The lifting fingers 147 lower and transfer the etchedsubstrate to the heated substrate support assembly 132.

At box 1050, a thermal treatment process is performed on the etchedsubstrate to remove the halogen-containing residues on the etchedsubstrate surface. The heater 135 in the heated substrate supportassembly 132 is used to cause the temperature of the surface of thesubstrate to rise, thereby causing halogen-based reactants disposed onthe etched substrate surface to be released and/or outgassed. The heatedsubstrate support assembly 132 heats the substrate to a temperaturebetween about 20 degrees Celsius and about 1000 degrees Celsius, such asbetween about 150 degrees Celsius and about 300 degrees Celsius, forexample about 250 degrees Celsius, at between about 5 seconds and about30 seconds. The rapid heating of the substrate by heated substratesupport assembly 132 allows the halogen-containing residues on theetched substrate to be removed without increasing process cycle timewhich would be encountered if the residues were removed in one if theprocessing chambers. In one embodiment, the substrate may be heated bythe heated substrate support assembly 132 at a predetermined time perioduntil the halogen-containing residues on the etched substrate areremoved therefrom. The time or endpoint may be determined using thesensors connected to the sensor signal receiver 139. The etchedsubstrate may be heated at a temperature between about 150 degreesCelsius and about 300 degrees Celsius, such as 250 degrees Celsius forbetween about 10 seconds to about 120 seconds, such as between about 30seconds to about 90 seconds.

In one embodiment, the gas mixture may be provided to the second chambervolume 120 of the dual load lock chamber 100 through the remote plasmasource 130. The remote plasma source 130 ionizes the gas mixture. Thedissociated ions and species promote the conversion of the outgassedhalogen-based reactants into non-corrosive volatile compounds, therebyincreasing the removal efficiency of the halogen-containing residuesfrom the etched substrate surface. The gas mixture may include anoxygen-containing gas, such as O₂, O₃, water vapor (H₂O), ahydrogen-containing gas, such as H₂, forming gas, water vapor (H₂O),alkanes, alkenes, and the like, or an inert gas, such as a nitrogen gas(N₂), argon (Ar), helium (He), and the like. For example, the gasmixture may include oxygen, nitrogen, and a hydrogen-containing gas. Inone embodiment, the hydrogen-containing gas is at least one of hydrogen(H₂) and water vapor (H₂O). In embodiments which mask layers is presenton the substrate, the mask layers may be simultaneously removed with thehalogen-containing residues, e.g., the mask is stripped of thephotoresist in the load lock chamber.

In one embodiment, the remote plasma source may provide a plasma powerat between about 500 Watts and 6000 Watts. In embodiments where theplasma is present, an inert gas, such as Ar, He or N₂, may be suppliedwith the gas mixture.

Alternatively, when dual load lock chamber 800 is used in place of thedual load lock chamber 100, a gas mixture may be supplied from the gassource 812 to the second chamber volume 120 while heating the etchedsubstrate. The etched substrate is exposed to and reacts with the gasmixture. The gas mixture converts the outgassed halogen-based reactantsinto non-corrosive volatile compounds that are pumped out of the dualload lock chamber 100.

Optionally, the substrate may be returned to one of the processingchamber 918 of the system for additional processing prior to removingfrom the vacuum environment. The substrate, after the halogen removalprocess at box 1050, will not introduce halogens into the processingchambers during subsequent processing, thereby preventing damage to theprocessing chambers.

At box 1060, the second chamber volume 120 is vented to atmosphericpressure. Optionally, the heated substrate support assembly 132 may becooled to lower the substrate temperature to a desired level through thecooling adaptor 141 during venting. In one embodiment, the etchedsubstrate may be cooled to a temperature ranging between about 10degrees Celsius and about 125 degrees Celsius that allows the etchedsubstrate returning to the FOUPs 906 without causing damage to the FOUPs906.

At box 1070, the etched substrate from the second chamber volume 120 ofthe load lock chamber 100 and return to one of the FOUPs 906 once thepressures of the second chamber volume 120 and the factory interface 902are matched.

In another embodiment of the present invention, a photoresist removalprocess may be performed in the dual load lock chamber according toembodiments of the present invention. FIG. 11 is a flow diagramillustrating a method 1100 including removing photoresist from asubstrate in a load lock chamber as the substrate exits a substrateprocessing system, such as the substrate processing system 900 of FIG.9.

The method 1100 is similar to the method 1000 of FIG. 10 except themethod 1100 includes an ashing process described in box 1150.

At box 1150, an ashing process is performed in the second chamber volume120 of the dual load lock chamber 100 to remove photoresist from thesubstrates. An oxygen-based plasma may be used. For example, anoxidizing gas such as O₂, is flown to the remote plasma source 130 at aflow rate of 100 to 10,000 sccm. The oxidizing gas is formed into aplasma when 600 to 6000 watts of RF energy is applied to the remoteplasma source 130. The gas pressure in the second chamber volume 120 maybe maintained at 0.3 to 3 Torr. The temperature of the substrate may bemaintained at 15 to 300 degrees Celsius. Various oxidizing gases can beused including, but not limited to, O₂ O₃, N₂O, H₂O, CO, CO₂, alcohols,and various combinations of these gases. In other embodiments of theinvention, nonoxidizing gases may be used including, but not limited to,N₂, H₂O, H₂, forming gas, NH₃, CH₄, C₂H₆, various halogenated gases(CF₄, NF₃, C₂F₆, C₄F₈, CH₃F, CH₂F₂, CHF₃), combinations of these gasesand the like.

The method 1000 or 1100 may incorporate the dual load lock chamber 100by using the first chamber volume 110 exclusively for incomingsubstrates and using the second chamber volume 120 exclusively foroutgoing substrates. By keeping the incoming and outgoing substrates inseparate paths, embodiments of the present invention effectively preventcross-contamination between processed and unprocessed substrates.

While the foregoing is directed to embodiments of the present invention,other and further embodiments of the invention may be devised withoutdeparting from the basic scope thereof, and the scope thereof isdetermined by the claims that follow.

1. A load lock chamber, comprising: a chamber body defining a firstchamber volume and a second chamber volume isolated from one another,wherein the first chamber volume is selectively connectable to twoprocessing environments through two openings configured for substratetransferring, and the second chamber volume is selectively connected toat least one of the two processing environments; a heated substratesupport assembly disposed in the second chamber volume, wherein theheated substrate support assembly is configured to support and heat asubstrate thereon; and a remote plasma source connected to the secondchamber volume for supplying a plasma to the second chamber volume. 2.The load lock chamber of claim 1, further comprising a thermal insulatordisposed within the second chamber volume between the heated substratesupport assembly and the chamber body, wherein the heated substratesupport assembly does not directly contact the chamber body.
 3. The loadlock chamber of claim 2, wherein the chamber body comprises: a firstchamber body having a top wall, sidewalls, and a chamber bottom, whereinthe top wall, sidewalls and chamber bottom define the first chambervolume; a second chamber body stacked on the top wall of the firstchamber body, wherein the second chamber body and the top wall of thefirst chamber body define the second chamber volume.
 4. The load lockchamber of claim 3, wherein the heated substrate support assemblycomprises: an upper heater plate having an upper surface for supportinga substrate thereon; a lower heater plate attached to a lower surface ofthe upper heater plate; and a heater disposed between the upper heaterplate and the lower heater plate.
 5. The load lock chamber of claim 4,wherein the heated substrate support assembly further comprises acantilever tube attached to a center of the lower heater plate.
 6. Theload lock chamber of claim 4, wherein the heated substrate supportassembly further comprises a chucking mechanism configured to chuck thesubstrate to the upper surface of the upper heater plate.
 7. The loadlock chamber of claim 3, further comprising a showerhead is disposedwithin a central opening defined by the second chamber body, and theshowerhead is configured to provide processing gas to the second chambervolume.
 8. The load lock chamber of claim 3, further comprising a lampassembly disposed above the second chamber body and configured toprovide radiant energy towards the second chamber volume.
 9. The loadlock chamber of claim 3, wherein a lower vacuum port is formed throughthe chamber bottom of the first chamber body, and the lower vacuum portprovides a pumping channel to the first chamber volume.
 10. The loadlock chamber of claim 9, wherein an upper vacuum port is formed throughthe sidewalls of the first chamber body, the upper vacuum port opens tothe second chamber volume.
 11. The load lock chamber of claim 1, furthercomprising a lift hoop assembly disposed in the second chamber volume,wherein the lift hoop assembly comprises a hoop body attached to a lift,and the hoop body surrounds the heated substrate support assembly. 12.The load lock chamber of claim 11, wherein the lift hoop assemblyfurther comprises three or more lifting fingers extending verticallydownward and radially inward from the hoop body, and the three or morelifting fingers are configured to receive and support a substrate. 13.The load lock chamber of claim 11, wherein the lift hoop assemblyfurther comprises a hoop liner attached to the hoop body, and the hoopliner extends upwards from the hoop body and provides a circularconfinement wall around the heated substrate support assembly.
 14. Theload lock chamber of claim 13, wherein the second chamber volume isselectively connected to the two processing environments throughopenings configured for substrate transferring.
 15. A method forremoving halogen-containing residues from a substrate, comprising:transferring a substrate to a substrate processing system through afirst chamber volume of a load lock chamber coupled to the substrateprocessing system, wherein the load lock chamber, comprising: a chamberbody defining the first chamber volume and a second chamber volumeisolated from one another, wherein the first chamber volume isselectively connectable to two processing environments through twoopenings configured for substrate transferring, and the second chambervolume is selectively connected to at least one of the two processingenvironments; a heated substrate support assembly disposed in the secondchamber volume, wherein the heated substrate support assembly isconfigured to support and heat a substrate thereon; and a remote plasmasource connected to the second chamber volume for supplying a plasma tothe second chamber volume; etching the substrate in the substrateprocessing chamber with chemistry comprising halogen; and removinghalogen-containing residues from the etched substrate in the secondchamber volume of the load lock chamber, wherein removinghalogen-containing residues comprises: heating the etched substrate on aheated substrate support assembly disposed in the second chamber volume;and flowing a processing gas to the second chamber volume.
 16. Themethod of claim 15, further comprising disposing a thermal insulatorwithin the second chamber volume between the heated substrate supportassembly and the chamber body, wherein the heated substrate supportassembly does not directly contact the chamber body.
 17. The method ofclaim 16, further stacking a first chamber body and a second chamberbody to form the chamber body, wherein the first chamber body comprisesa top wall, sidewalls, and a chamber bottom, and the top wall, sidewallsand chamber bottom define the first chamber volume, and the secondchamber body and the top wall of the first chamber body define thesecond chamber volume.
 18. The method of claim 17, further comprisingpumping the first chamber volume through a lower vacuum port formedthrough the chamber bottom of the first chamber body.
 19. The method ofclaim 17, further comprising pumping the second chamber volume throughan upper vacuum port formed through the sidewalls of the first chamberbody.
 20. The method of claim 15, further comprising receiving andsupporting the substrate by three or more lifting fingers of lift hoopassembly disposed in the second chamber volume, wherein the lift hoopassembly comprises a hoop body attached to a lift, and the hoop bodysurrounds the heated substrate support assembly.